Minimally invasive sacroiliac joint fusion: one-year outcomes in 18 patients

BACKGROUND: Sacroiliac joint (SI) pain is an often-overlooked cause of low back pain due, in part, to lack of specific findings on radiographs and symptoms mimicking other back-related disorders. We report our experience with minimally invasive (MIS) SI joint arthrodesis using a series of triangular, titanium plasma spray (TPS) coated implants in patients refractory to conservative care. METHODS: We report outcomes from 18 patients with 12 months of postoperative follow-up. Demographics, complications, and clinical outcomes using visual analog scale (VAS) for pain, Oswestry Disability Index (ODI) for back function and SF-12 for quality of life were collected preoperatively and at 3, 6 and 12 months post-operatively. RESULTS: Mean age was 64 years and 67% of patients were female. There were no intraoperative complications and one explant at three months for malposition. All patient-reported outcomes showed both clinically and statistically significant improvement at 12 months (p < 0.001 for each of the following): VAS improved by 6.6 points, ODI scores improved by −37.5 points. One year SF-12 physical and mental component (PCS, MCS) scores approximated population normal scores for both physical and mental functioning. Patient satisfaction with outcomes was high at 95%; 89% said would have the same surgery again. CONCLUSIONS: MIS SI joint fusion using a series of triangular porous TPS coated titanium implants is a safe and effective procedure for patients with SI joint disorders who have failed conservative care

Optically stimulated nanodosimeters with high storage capacity

In this work we report on the thermoluminescence (TL) and optically stimulated luminescence (OSL) properties of beta-Na(Gd,Lu)F-4:Tb3+ nanophosphors prepared via a standard high-temperature coprecipitation route. Irradiating this phosphor with X-rays not only produces radioluminescence but also leads to a bright green afterglow that is detectable up to hours after excitation has stopped. The storage capacity of the phosphor was found to be (2.83 +/- 0.05) x 10(16) photons/gram, which is extraordinarily high for nano-sized particles and comparable to the benchmark bulk phosphor SrAl2O4:Eu2+,Dy3+. By combining TL with OSL, we show that the relatively shallow traps, which dominate the TL glow curves and are responsible for the bright afterglow, can also be emptied optically using 808 or 980 nm infrared light while the deeper traps can only be emptied thermally. This OSL at therapeutically relevant radiation doses is of high interest to the medical dosimetry community, and is demonstrated here in uniform, solution-processable nanocrystals

Counting the photons : determining the absolute storage capacity of persistent phosphors

The performance of a persistent phosphor is often determined by comparing luminance decay curves, expressed in cd/m(2). However, these photometric units do not enable a straightforward, objective comparison between different phosphors in terms of the total number of emitted photons, as these units are dependent on the emission spectrum of the phosphor. This may lead to incorrect conclusions regarding the storage capacity of the phosphor. An alternative and convenient technique of characterizing the performance of a phosphor was developed on the basis of the absolute storage capacity of phosphors. In this technique, the phosphor is incorporated in a transparent polymer and the measured afterglow is converted into an absolute number of emitted photons, effectively quantifying the amount of energy that can be stored in the material. This method was applied to the benchmark phosphor SrAl2O4: Eu, Dy and to the nano-sized phosphor CaS: Eu. The results indicated that only a fraction of the Eu ions (around 1.6% in the case of SrAl2O4: Eu, Dy) participated in the energy storage process, which is in line with earlier reports based on X-ray absorption spectroscopy. These findings imply that there is still a significant margin for improving the storage capacity of persistent phosphors

Heme Nitrosylation of Deoxyhemoglobin byS-Nitrosoglutathione Requires Copper

NO reactions with hemoglobin (Hb) likely play a role in blood pressure regulation. For example, NO exchange between Hb and S-nitrosoglutathione (GSNO) has been reported in vitro. Here we examine the reaction between GSNO and deoxyHb (HbFeII) in the presence of both Cu(I) (2,9-dimethyl-1, 10-phenanthroline (neocuproine)) and Cu(II) (diethylenetriamine-N,N,N′,N",N"-pentaacetic acid) chelators using a copper-depleted Hb solution. Spectroscopic analysis of deoxyHb (HbFeII)/GSNO incubates shows prompt formation (<5 min) of ∼100% heme-nitrosylated Hb (HbFeIINO) in the absence of chelators, 46% in the presence of diethylenetriamine-N,N,N′,N",N"-pentaacetic acid, and 25% in the presence of neocuproine. Negligible (<2%) HbFeIINO was detected when neocuproine was added to copper-depleted HbFeII/GSNO incubates. Thus, HbFeIINO formation via a mechanism involvingfree NO generated by Cu(I) catalysis of GSNO breakdown is proposed. GSH is a source of reducing equivalents because extensive GSSG was detected in HbFeII/GSNO incubates in the absence of metal chelators. No S-nitrosation of HbFeII was detected under any conditions. In contrast, the NO released from GSNO is directed to Cysβ93 of oxyHb in the absence of chelators, but only metHb formation is observed in the presence of chelators. Our findings reveal that the reactions of GSNO and Hb are controlled by copper and that metal chelators do not fully inhibit NO release from GSNO in Hb-containing solutions

High resolution fluorescence imaging of cancers using lanthanide ion-doped upconverting nanocrystals

During the last decade inorganic luminescent nanoparticles that emit visible light under near infrared (NIR) excitation (in the biological window) have played a relevant role for high resolution imaging of cancer. Indeed, semiconductor quantum dots (QDs) and metal nanoparticles, mostly gold nanorods (GNRs), are already commercially available for this purpose. In this work we review the role which is being played by a relatively new class of nanoparticles, based on lanthanide ion doped nanocrystals, to target and image cancer cells using upconversion fluorescence microscopy. These nanoparticles are insulating nanocrystals that are usually doped with small percentages of two different rare earth (lanthanide) ions: The excited donor ions (usually Yb3+ ion) that absorb the NIR excitation and the acceptor ions (usually Er3+, Ho3+ or Tm3+), that are responsible for the emitted visible (or also near infrared) radiation. The higher conversion efficiency of these nanoparticles in respect to those based on QDs and GNRs, as well as the almost independent excitation/emission properties from the particle size, make them particularly promising for fluorescence imaging. The different approaches of these novel nanoparticles devoted to "in vitro" and "in vivo" cancer imaging, selective targeting and treatment are examined in this reviewJ.A.C. is a Concordia University Research Chair in Nanoscience and is grateful to Concordia University for financial support of his research. J.A.C. and F.V. are grateful for financial support from the Natural Sciences and Engineering Research Council (NSERC) of Canada. R.N. is grateful for NSERC financial support through the Alexander Graham Bell Graduate Scholarship Program. B.F.Z. is grateful to les Fonds Québécois de Recherche sur la Nature et les Technologies (FQRNT) for financial support through the Graduate Scholarship Program. This work was also supported in part by the Universidad Autónoma de Madrid and Comunidad Autónoma de Madrid (Projects CCG087-UAM/MAT-4434 and S2009/MAT-1756), by the Spanish Ministerio de Educación y Ciencia (MAT 2010–16161). EMR acknowledges financial support from Fundación Alfonso Martín Escudero and Marie Curie IOF Fellowship Program (project 274404 LUNAMED

Structural investigation and Anti-Stokes emission of scandium oxide nanocrystals activated with trivalent erbium

The structural and emission (Stokes and anti-Stokes) properties of Sc2O3: Er3+ nanocrystals doped with 0.1, 1, and 10 mol % Er3+ were investigated. The nanocrystalline powders were characterized using X-ray scattering as well as transmission and scanning electron microscopy. The samples showed a very porous, open microstructure with the particles having a narrow distribution of sizes (10-60 nm). Furthermore, the mechanisms responsible for the anti-Stokes emission (lambda(exc) = 980 nm) were elucidated. We observed that the processes responsible for populating the green (H-2(11/2), S-4(3/2)) and red (F-4(9/2)) emitting states were dependent upon the concentration of the dopant ion. In 0.1 mol % nanocrystalline Sc2O3: Er3+, upconversion was determined to occur via excited state absorption while in the 10 mol % sample, energy transfer upconversion was the dominant mechanism. An enhancement of the red anti-Stokes emission from the F-4(9/2) --> I-4(15/2) transition was observed in Sc2O3: Er3+ nanocrystals as a function of Er3+ concentration. This was the result of two independent processes responsible for directly populating the F-4(9/2) state and bypassing the green emitting levels (H-2(11/2) and S-4(3/2)). Furthermore, the red enhancement was found to be more pronounced compared to identically doped Y2O3: Er3+ nanocrystals. An explanation for this phenomenon is presented and discussed

Nanoparticles for highly efficient multiphoton fluorescence bioimaging

In this paper, we demonstrate for the first time that the new class of fluoride-based inorganic upconverting nanoparticles, NaYF4:Er3+, Yb3+, are the most efficient multiphoton excited fluorescent nanoparticles developed to date. The near-infrared-to-visible conversion efficiency of the aforementioned nanoparticles surpasses that of CdSe quantum dots and gold nanorods, which are the commercially available inorganic fluorescent nanoprobes presently used for multiphoton fluorescence bioimaging. The results presented here open new perspectives for the implementation of fluorescence tomography by multiphoton fluorescence imaging

Why High-Performance Modelling and Simulation for Big Data Applications Matters

Modelling and Simulation (M&S) offer adequate abstractions to manage the complexity of analysing big data in scientific and engineering domains. Unfortunately, big data problems are often not easily amenable to efficient and effective use of High Performance Computing (HPC) facilities and technologies. Furthermore, M&S communities typically lack the detailed expertise required to exploit the full potential of HPC solutions while HPC specialists may not be fully aware of specific modelling and simulation requirements and applications. The COST Action IC1406 High-Performance Modelling and Simulation for Big Data Applications has created a strategic framework to foster interaction between M&S experts from various application domains on the one hand and HPC experts on the other hand to develop effective solutions for big data applications. One of the tangible outcomes of the COST Action is a collection of case studies from various computing domains. Each case study brought together both HPC and M&S experts, giving witness of the effective cross-pollination facilitated by the COST Action. In this introductory article we argue why joining forces between M&S and HPC communities is both timely in the big data era and crucial for success in many application domains. Moreover, we provide an overview on the state of the art in the various research areas concerned

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries